Optical fiber is a very popular medium for large bandwidth applications, and as a result there is a demand for fiber optic cables with greater numbers of optical fibers. In response to demands for increased optical fiber count in fiber optic cables, optical fiber ribbons have been developed. Optical fiber ribbons are planar arrays of optical fibers that are bonded together as a unit. Optical fiber ribbons are advantageous because many ribbons can be stacked on top of each other to form a stack of optical fiber ribbons.
It is conventional for stacks of optical fiber ribbons to be incorporated into two different types of fiber optic cables that are generally referred to as "central-core" and "loose-tube" cables. In the central-core design, a stack of optical fiber ribbons are contained within a central tube, which is located at the center of the fiber optic cable. Further, strength members are positioned between the central tube and an outer plastic jacket of the cable. In contrast, loose-tube fiber optic cables typically include a number of relatively small buffer tubes that are positioned around a central strength member, and each buffer tube encloses a stack of optical fiber ribbons. The buffer tubes are longitudinally stranded around the central strength member, meaning that the buffer tubes are rotated around the central strength member along the length of the fiber optic cable.
In an effort to increase the density of optical fibers within fiber optic cables, different arrangements of stacks of optical fiber ribbons have been proposed. For example, U.S. Pat. No. 5,878,180 discloses a fiber optic cable with uniform stacks of optical fibers in side-by-side arrangements.
Whereas advancements have been made in the area of increasing the density of optical fibers within fiber optic cables, further advancements and options in this area would be beneficial.